Two kinds of retractors are presently used in surgery: hand-held retractors and self-locking tongs. The hand-held retractors are simply a pair of hooks which are inserted at the desired positions under the edge of a cut or wound and held by a nurse or assistant while the surgeon operates. Aside from the additional person required to hold them, such retractors only hold the cut open at two points, unless, of course, additional people and retractors are employed.
Self-locking tong retractors, while not requiring additional people, hold the cut open at only two opposing points. The tong retractors have hooks at the tong ends which are inserted under the cut edge. The ends of the tongs are then spread apart, thereby opening the cut. The tong hinge is fitted with a self-locking ratchet or spring mechanism to hold the wound open. One disadvantage of tong retractors is that it is easy to apply excessive stress to the skin or tissue exposed by the cut with them. Another important disadvantage is the excessive bulk of such devices in the surgical field.
This problem is particularly important with virtually all retractors employed in limb surgery. When the retractors must be used so as to separate the incision, such retractors are often in an awkward and cumbersome position. The position of the retractor can often adversely affect the surgical procedure and creates an obstruction to the observation and viewing of the incision. If persons are employed for the purpose of maintaining the open incision, then this further impedes the surgical process.
In the past, however, various U.S. Patents have been issued with respect to retractor instruments for the exposing of a surgical incision.
U.S. Pat. No. 3,762,401, issued Oct. 2, 1973 to J. W. Tupper shows a surgical retractor for use in hand surgery. This retractor includes a paddle-shaped pallet with notches around the periphery on which the hand is placed, wound-side up. Elastic bands are provided for holding the fingers in place on the pallet. At least one flexible ball-and-link chain with a hook at one end is hooked over the edge of the wound and is fastened to a pallet edge at a predetermined point along its length. An arrangement of such hooks thereby holds the wound open.
U.S. Pat. No. Re. 32,021 also shows a surgical retractor which has a frame conformed to fit the surface contour of the portion of the body to be operated on. A stay is provided which includes an elastic member and suitable tissue holding means. The frame has a plurality of notches spaced around its periphery. The elastic member of the stay is adapted to be inserted into one of the notches and held in place by friction so as to retract the tissue.
U.S. Pat. No. 2,695,607, issued on Nov. 30, 1954 to Hipps et al shows a bone retractor formed of two members which has an offset and a curved portion. This offset portion is adapted so as to engage the underside of a bone. The members extend through the incision to the underside of the bone. A chain engages notches formed on the member. This chain is adapted so as to extend around the periphery of the limb for the purpose of retaining the members in an outward position.
U.S. Pat. No. 2,612,891, issued on Oct. 7, 1952, to M. C. Smith, describes an adjustable support for finger surgery. In particular, a pair of retractor members are fastened within binding posts. By locking a thumb screw in position, the retractors are maintained in an outward position.
Soviet Patent No. 1360-706-A discloses a wound dilator in which a rod is bent along a radius and is equipped with a tubular guide bent along the same radius. A threaded end with a slit is provided on the tubular guide. A fastener, in the form of a nut with an inner cone, is set on the threaded end of the guide. A hinge mechanism is provided so as to allow the wound dilator to engage the edges of the incision.
It is an object of the present invention to provide a retractor instrument which is suitable for maintaining a surgical incision in an open position.
It is another object of the present invention to provide a surgical retractor which does not impede, interfere with, or obstruct the surgical field.
It is another object of the present invention to provide a surgical retractor which is adjustable in a position distal from the incision.
It is still a further object of the present invention to provide a surgical retractor which distributes the retracting force against a large area of the incision.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.